Value of cystatin C in predicting atrial fibrillation recurrence after radiofrequency catheter ablation

BACKGROUD: Recent studies have demonstrated that cystatin C is a valuable risk marker for cardiovascular disease morbidity and mortality. Therefore, we hypothesized that the pre-ablation cystatin C level was associated with post-ablation atrial fibrillation (AF) recurrence. METHODS: 207 patients were enrolled and completed in this prospective observational study. Patients with AF scheduled for receive radiofrequency catheter ablation (RFCA) therapy were screened for the study. Before ablation therapy, electrocardiogram, 24 h holter monitor, transesophageal echocardiography, serum cystatin C, high-sensitivity C-reactive protein, creatinine levels, and routine blood examinations were examined. After ablation, patients were followed up every week for the first month, and then at 2, 3, 6, 9, and 12 months. Thereafter, patients came back to out-patient clinic every six months regularly. Electrocardiogram or 24 h holter monitor were repeated if the patient experienced palpitations or every six months. AF recurrence was defined as atrial fibrillation/atrial flutter or atrial tachycardia lasting ≥ 30 seconds within three months after therapy. RESULTS: Compared to patients with no AF recurrence, patients with recurrence had longer AF history (P = 0.007), more early recurrence (P = 0.000), a larger left atrium (P = 0.004), and higher pre-ablation cystatin C levels (P = 0.000). Multivariate regression analysis revealed that cystatin C and left atria (LA) diameter were risk factors for AF recurrence. After adjusting for LA diameter, the risk of AF recurrence increased 30% with every milligram cystatin C elevation (95% CI: 1.117–1.523). CONCLUSIONS: Pre-ablation cystatin C levels were associated with AF recurrence after RFCA therapy, an optimal cut-off value of 1.190 mg/L (sensitivity = 0.576; specificity = 0.851).